Initiate the script that takes a snapshot of CPU usage

scripts/slave/recipe_modules/auto_bisect/resources/cpu_usage.py

+#!/usr/bin/python
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Prints out the most active processes running in the background.
+
+Example usage:
+  ./cpu_usage.py --nproc==[THE NUMBER OF PROCESSES TO PRINT OUT]
+"""
+
+
+import argparse
+import json
+import platform
+import subprocess
+import sys
+
+LINUX_START_LINE_NUM = 7
+WINDOWS_START_LINE_NUM = 3
+
+def _parse_line(line):
+  """Parses a line from top output
+
+  Args:
+    line(str): a line from top output that contains the
+    information of a process
+
+  Returns:
+    An dictionary with useful information about the process
+
+  """
+  token_list = line.strip().split()
+  if platform.system() == "Windows":
+    process_object = {'pid':token_list[6],
+                      'pCPU':token_list[5],
+                      'command':token_list[7]}
+  else:
+    process_object = {'pid':token_list[0], 'user':token_list[1],
+                      'pCPU':token_list[8], 'pMEM':token_list[9],
+                      'command':token_list[11]}
+  return process_object
+
+def _get_top_processes(n):
+  """Fetches the top processes returned by top command
+
+  Args:
+    n(int): the number of processes to get
+
+  Returns:
+    A list of dictionaries, each representing one of the top processes
+
+  """
+  if platform.system() == "Windows":
+    processes = subprocess.check_output('powershell "ps | sort -desc cpu"',
+                                            shell=True).split('\n')
+    top_processes = processes[WINDOWS_START_LINE_NUM:
+                              WINDOWS_START_LINE_NUM + n]
+  else:
+    processes = subprocess.check_output(["top","-n 1","-b"]).split('\n')
+    top_processes = processes[LINUX_START_LINE_NUM:
+                              LINUX_START_LINE_NUM + n]
+    parsed_top_processes = [_parse_line(process) \
+                            for process in top_processes]
+    return parsed_top_processes
+
+
+def main():
+  parser = argparse.ArgumentParser(
+  description='Take a snapshot of CPU usage.')
+  parser.add_argument('--nproc', dest='nproc', default=10,
+                      help='the number of processes to display')
+  args = parser.parse_args()
+  top_processes = _get_top_processes(int(args.nproc))
+  print(json.dumps(top_processes))
+  return 0
+
+if __name__ == "__main__":
+  main()